Can Retail RUSE Be Entered into Steam?
Can the retail version of RUSE be entered into Steam?
It depends. The Steam Store support article about CD keys supported by Steam mentions the following:
R.U.S.E. CD Keys in this format:
Note: R.U.S.E. keys from Ubisoft's Digital River service are not accepted on Steam
If your retail key is in a different format or if you bought the game from the Ubisoft store, well, tough luck.